The CFL LT Designer with Monte Carlo is a practically-oriented design tool for the Linkwitz Transform biquad circuit that includes a Monte Carlo sensitivity analysis.

To design the circuit, the user follows a series of steps. Statistics are presented on the values for the LT parameters that can be expected when the circuit is built from real-world components with finite tolerances. Capacitors values can come from E6, E12, or E24 values. All resistors are chosen from the E96 series. Several informative plots are provided that highlight the level of accuracy that can be expected from the as-built circuit.

Three options are provided for the circuit that provide different levels of complexity and accuracy of capacitor and resistor values compared to "ideal" values.

Mismatches between the "ideal" values and those that can be obtained in a discrete series (e.g. E96 resistors) are one source of error. The other source of error is the actual value of the component due to finite tolerance around the series value. Using a Monte Carlo approach, the variation in error that can be expected from component tolerances is presented. For most cases, the errors resulting from component tolerances are significantly higher than the errors resulting from the choice of the scaling factor and the discrete nature of real world component values. The spreadsheet helps the user make tradeoffs between complexity and cost of the circuit design, to identify which components to purchase, and to establish bounds for the performance of the as-built circuit. The statistics help the user to improve both the accuracy, and the precision, of the resulting analog circuit.

Currently, only an Excel version is available for Excel 2003 and later, and requires the Analysis Toolpak.